Evaluation of effect of number of electrodes in ERT sensors on image quality

It is assumed that the spatial resolution of the reconstructed images with an electrical resistance tomography (ERT) system can be improved by increasing the number of measurement electrodes. In this paper, the issues with the number of electrodes will be discussed. To analyze the effect of the number of electrodes on the quality of reconstructed images, ERT sensors with different number of electrodes-8, 12, 16, 20, 24, 32, 36, 40 and 48-are investigated. With the adjacent and opposite strategies, the voltages between different electrode pairs are calculated for some typical conductivity distributions with different contrast in conductivity using a finite element method. The obtained voltage data are then used to reconstruct images using the projected Landweber iteration algorithm. In the meanwhile, the impact of meshes in the inverse problem solver on image quality is also discussed. The sensitivity distributions for all cases are analyzed utilizing singular value decomposition (SVD). The analytical results are in agreement with the simulation results.